DE102011003053A1 - Device for changing the relative angular position of a camshaft relative to a crankshaft of an internal combustion engine - Google Patents

Abstract

The invention relates to a device (1) for changing the relative angular position of a camshaft (2) with respect to a crankshaft of an internal combustion engine, the device (1) having a drive element (3) driven by the crankshaft and a rotor connected in a rotationally fixed manner to the camshaft (2) (4), at least two hydraulic chambers (5, 6) being formed between the drive element (3) and the rotor (4), which can be hit with a pressurized fluid in order to achieve a defined relative rotational position between the drive element (3) and the rotor (4) to set, and wherein fluid channels (7) are formed between a pressurized fluid source and the hydraulic chambers (5, 6). In order to minimize the axial installation space, to achieve a simple configuration of the fluid channels and to avoid contamination of the oil circuit, the invention provides that at least one section of at least one fluid channel (7) between an end-face area (8) of the rotor (4) and an insert element (9) is formed, which is attached to the end region (8) of the rotor (4).

Description

Field of the invention

The invention relates to a device for changing the relative angular position of a camshaft relative to a crankshaft of an internal combustion engine, wherein the device comprises a driven by the crankshaft drive element and a non-rotatably connected to the camshaft rotor, wherein between the drive element and the rotor at least two hydraulic chambers are formed, which can be beached with a pressurized fluid in order to set a defined relative rotational position between the drive element and the rotor, and wherein between a pressure fluid source and the hydraulic chambers fluid channels are formed.

Background of the invention

In internal combustion engines mostly camshaft adjusting devices are used, in particular those which operate hydraulically. Examples of this reveal the DE 198 29 049 A1 and the US 5,931,126 , If the camshaft adjuster - which is typical - works hydraulically, it has an impeller in which wings are molded or arranged. The wings are located in hydraulic chambers, which are incorporated in a drive element (also called external rotor or stator). By appropriate action on the respective side of the hydraulic chambers with hydraulic fluid, an adjustment of the inner rotor (connected to the camshaft) can take place relative to the outer rotor between an "early stop" and a "late stop". The flow of hydraulic oil is controlled by an electrically controlled directional control valve. The transmission of the rotational movement of the crankshaft to the outer rotor is usually via a gear, with which the outer rotor is rotatably connected.

Between the input and output part of the camshaft adjuster a spring is often arranged, one end of which is supported directly or indirectly on the drive part and the other end directly or indirectly on the driven part, so that a provision of the drive or driven part is ensured in a basic position , To accommodate the spring, a spring receiving space is formed in a camshaft adjuster. Such a solution shows the DE 10 2008 051 142 A1 ,

It is possible according to an embodiment of the camshaft adjuster to provide a separate receiving space for the spring. The advantage of this solution is a separation of the area of the spring from the oil supply and removal. However, this requires a higher axial space and thus has a higher weight of the camshaft adjuster result. Furthermore, for the oil supply and removal stepped bores are necessary, which are expensive to produce.

Another embodiment of the camshaft adjuster provides that the spring receiving chamber is traversed by oil in its path into the hydraulic chambers (integrated spring housing). A disadvantage of this solution is that more oil is needed for the supply of hydraulic chambers, since the spring receiving space must first be filled. Furthermore, it is negative that dirt or chips, which may be incurred during assembly, can get into the oil circuit.

In order to carry out weight-reducing measures on the rotor of the camshaft adjuster, the oil supply of the two hydraulic chambers in the camshaft adjuster is limited by bores. A depression that would pass through one of the two supply bores is beneficial to the weight of the phaser, however, at engine startup, the system requires more oil through the volume thus created in the rotor, which can slow the system down to the spring or weight relieving chamber filled with oil.

Object of the invention

The present invention has the object, a device of the type mentioned in such a way that it is possible to avoid the disadvantages mentioned. Accordingly, a small axial space and thus a low weight of the camshaft adjuster should be achieved. The fluid channels to the hydraulic chambers should be able to be easily configured. Special attention is also paid to avoid contamination of the oil circuit by dirt or chips during assembly.

Summary of the invention

The solution of this problem by the invention is characterized in that at least one. Section of at least one fluid channel between an end region of the rotor and an insert element is formed, which is fixed to the frontal region of the rotor.

The insert element is preferably designed as a pot-shaped component.

It may be arranged with a centering portion in an annular groove-shaped recess at the axial end of the rotor.

The insert element may have an annular receptacle. This is preferred provided in order to arrange in her a spring element, in particular a torsion spring.

At least one radially extending fluid channel portion may be formed as a groove in a first end portion of the rotor. At least one further radially extending fluid channel section may be formed as a groove in a second end section of the rotor, which is arranged offset axially relative to the first end section. Furthermore, at least one axially extending fluid channel section may be formed as a groove in a first axially extending section of the rotor in its frontal region. At least one further axially extending fluid channel section may be formed as a groove in a second axially extending section of the rotor in its frontal region, which is arranged offset radially relative to the first axially extending section.

The insert element is preferably formed as a thin-walled part. It is mostly made of metal or plastic. In the case of training as a plastic molded part of the injection molding process is usually used. In the embodiment of sheet metal stamping and / or thermoforming processes can be used for forming the insert element.

By using the insert element, in particular as a shaped sheet metal, one uses the created in the rotor. Free space to place the spring and also to transport the oil supply directly via grooves in the rotor in the respective hydraulic chamber of the camshaft adjuster, without having to fill the space with oil.

Furthermore, dirt or chips that arise during assembly of the camshaft adjuster, not supplied to the oil circuit, but held by the insert element.

The rotor is preferably provided with a recessed, uninterrupted shoulder (ringnutförmige recess). As a result, the insert element, which forms a dirt sheet, can be installed flush in the rotor. As a result, inexpensive and highly accurate machining (eg by grinding) of the rotor end face is possible. The resulting annular surfaces serve to seal the oil flow. The oil leakage is reduced by reducing the gap or by the use of sealing elements.

By changing the geometry of the insert element a variety of options is given; This is also a likelihood of confusion during assembly is not given.

The mentioned spring is not mandatory; they can also be dispensed with in appropriate designs. This results in additional weight advantages over conventional weight-saving measures.

Overall, there is thus no risk of contamination of the oil circuit through the use of the insert element during the assembly process. An uninterrupted supply of oil is also given in the presence of the internal spring.

The weight of the camshaft adjuster can be minimized.

At the. Starting the engine requires less oil.

Brief description of the figures

In the drawings, embodiments of the invention are shown. Show it:

1 in a radial sectional view of a phaser of an internal combustion engine according to a first embodiment of the invention, namely the section CD according to 2 .

2 the section AB according to 1 through the phaser,

3 in a radial sectional view of the camshaft adjuster according to a second embodiment of the invention, namely the section CD according to 4 .

4 the section AB according to 3 through the camshaft adjuster and

5 in a perspective view of the rotor of the camshaft adjuster.

Detailed description of the figures

In 1 and 2 is a first embodiment of a device 1 for changing the relative angular position of a camshaft 2 represented with respect to a crankshaft of an internal combustion engine, so a camshaft adjuster. The camshaft actuator 1 has a drive element in a known manner 3 (sometimes referred to as outer rotor or stator) and a rotor 4 which can twist relative to the stator. The rotor is in 5 shown. For details, reference is expressly made to the above-mentioned publications, where also explanations of the general operation of the camshaft adjuster can be found.

To a relative rotation between the drive element 3 and rotor 4 to accomplish, are several hydraulic chambers between Drive element and rotor formed by, on the rotor 4 arranged wings 19 are divided so that hydraulic chambers 5 and 6 form. Depending on the charge of the hydraulic chambers 5 and 6 the relative rotation between the drive element takes place 3 and rotor 4 ,

The hydraulic oil required for this purpose is via fluid channels 7 the respective chamber 5 . 6 fed. A fluid channel 7 consists of several fluid channel sections 7 ' . 7 '' . 7 ''' . 7 '''' . 7 ''''' and 7 '''''' , as it appears from the figures.

It is essential that at least a section of the fluid channel 7 between a frontal area 8th of the rotor 4 and an insert element 9 is formed, that at the frontal area 8th of the rotor 4 is attached.

The insert element 9 in the present case consists of a rotationally symmetrical component, in particular of a deep-drawn sheet metal part, which has a shape as shown in the radial section according to 1 is apparent. At the axial end 12 of the rotor 4 is a ringnutförmige recess 11 incorporated; the insert element 9 has a radially outer centering 10 on, the matching to the annular groove-shaped recess 11 is executed, so that the insert element 9 precisely fitting and centered in the frontal area 8th of the rotor 4 can be placed and fastened.

The shape of the insert element 9 makes it possible that an annular receptacle (with a substantially rectangular in radial section shape) is created, in which a spring element 14 is used in the form of a torsion spring.

The formation of the individual fluid channel sections results from the synopsis of 1 . 2 and 5 , The rotor 4 has a first frontal section 15 and an axially offset second end-side section 16 onto. 5 ). Equally, the rotor points 5 a first axially extending portion 17 and a second axially extending portion radially offset therefrom 18 on.

As in 5 Best seen are radially or axially extending grooves in the sections 15 . 16 . 17 and 18 incorporated, which form the fluid channel sections. Concretely, fluid channel sections 7 '''' in the section 15 , Fluid channel sections 7 '' in the section 16 , Fluid channel sections 7 ''' in the section 17 and fluid channel sections 7 ''''' in the section 18 incorporated, in each case four fluid channel section of each type, evenly distributed over the circumference, to the corresponding four hydraulic chambers 5 . 6 to supply with oil.

Will the insert element 9 mounted, said fluid channel sections are frontally or radially limited so that in them oil can be transported. Oil from a source of pressure oil, not shown, can thus into the hydraulic chambers 5 respectively. 6 or get back from them.

The entire arrangement can be made by a central screw 20 held together, which has a hole in the insert element 9 interspersed.

For the determination of the spring element 14 may be the insert element 9 have a Federeinhängungsausnehmung that can be made by forming. Optionally, also in the rotor 4 a corresponding Federeinhängungsausnehmung be provided.

In terms of manufacturing technology, it may be advantageous if the required grooves and possibly recesses are produced by means of a sintering process. After that, both the oil grooves (ie the fluid channel sections mentioned) and the optional spring suspension recess are produced by a sintering process. Subsequent processing becomes superfluous in this case.

In the 3 and 4 an alternative is shown, which differs essentially only in that no spring element 14 is available. Nevertheless, the insert element 9 the same education. The thus existing annular recording 13 fulfills the function of keeping the space to be filled with oil low.

LIST OF REFERENCE NUMBERS

1

Device for changing the relative angular position (camshaft adjuster)

2

camshaft

3

driving element

4

rotor

5

hydraulic chamber

6

hydraulic chamber

7

fluid channel

7 '

Fluid channel section

7 ''

Fluid channel section

7 '' '

Fluid channel section

7 '' ''

Fluid channel section

7 '' '' '

Fluid channel section

7 '' '' ''

Fluid channel section

8th

frontal area of the rotor

9

insert element

10

centering

11

ringnutförmige recess

12

axial end of the rotor

13

annular recording

14

spring element

15

first frontal section of the rotor

16

second frontal section of the rotor

17

first axially extending portion of the rotor

18

second axially extending portion of the rotor

19

wing

20

central screw

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19829049 A1 [0002]
• US 5931126 [0002]
• DE 102008051142 A1 [0003]

Claims (10)

Contraption ( 1 ) for changing the relative angular position of a camshaft ( 2 ) relative to a crankshaft of an internal combustion engine, wherein the device ( 1 ) a driven by the crankshaft drive element ( 3 ) and one with the camshaft ( 2 rotatably connected rotor ( 4 ), wherein between the drive element ( 3 ) and the rotor ( 4 ) at least two hydraulic chambers ( 5 . 6 ) are formed, which are beached with a pressurized fluid to a defined relative rotational position between the drive element ( 3 ) and the rotor ( 4 ) and wherein between a pressure fluid source and the hydraulic chambers ( 5 . 6 ) Fluid channels ( 7 ) are formed, characterized in that at least a portion of at least one fluid channel ( 7 ) between a frontal area ( 8th ) of the rotor ( 4 ) and an insert element ( 9 ) is formed, which at the frontal area ( 8th ) of the rotor ( 4 ) is attached. Device according to claim 1, characterized in that the insert element ( 9 ) is designed as a pot-shaped component. Device according to claim 1, characterized in that the insert element ( 9 ) with a centering section ( 10 ) in an annular groove-shaped recess ( 11 ) at the axial end ( 12 ) of the rotor ( 4 ) is arranged. Device according to claim 1, characterized in that the insert element ( 9 ) an annular receptacle ( 13 ) having. Apparatus according to claim 4, characterized in that in the annular receptacle ( 13 ) a spring element ( 14 ), in particular a torsion spring, is arranged. Apparatus according to claim 1, characterized in that at least one radially extending fluid channel section ( 7 '''' ) as a groove in a first frontal section ( 15 ) of the rotor ( 4 ) is trained. Apparatus according to claim 6, characterized in that at least one further radially extending fluid channel section ( 7 '' ) as a groove in a second frontal section ( 16 ) of the rotor ( 4 ) is formed, which relative to the first front-side section ( 15 ) is arranged offset axially. Apparatus according to claim 1, characterized in that at least one axially extending fluid channel section ( 7 ''' ) as a groove in a first axially extending portion (FIG. 17 ) of the rotor ( 4 ) in its frontal area ( 8th ) is trained. Apparatus according to claim 8, characterized in that at least one axially extending fluid channel section ( 7 ''''' ) as a groove in a second axially extending portion (FIG. 18 ) of the rotor ( 4 ) in its frontal area ( 8th ) formed relative to the first axially extending portion (FIG. 17 ) is arranged radially offset. Device according to claim 1, characterized in that the insert element ( 9 ) is formed as a thin-walled part, which consists of metal or plastic.

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